Making the Largest 3D Maps of our Universe

Dr. Josh Dillion will talk about a new technique being developed here at Berkeley with collaborators around the world to use radio telescopes to make huge 3D maps of hydrogen, the most abundant element in the universe, to test our cosmological theories. He will explain the observational challenges we’re facing and the reason why we’re building a giant array of 350 dishes - each one almost 50 feet across - in the middle of the South African desert. Along the way, he will discuss how we know what we know about cosmology today and how we use radio telescopes to map out that ancient hydrogen and see the impact that the very first stars, galaxies, and black holes had on it.

The last century has seen a revolution in our understanding of the universe and our place in it. We now know that the universe is about 13.8 billion years old and only about 5% normal matter - the stuff we’re made up of like protons, neutrons, electrons. Uncovering the nature of the other 95%, the mysterious dark matter and even more mysterious dark energy, is one of the most important questions in fundamental physics today.